Strength of the hanging wall, footwall, and ore body. Caving underground mining methods longwall, sublevel. Numerical simulation of independent advance of ore breaking. A stoping method in which relatively thin blocks of ore are caused to cave by successively undermining small panels. Block caving is an underground mining method applicable to the extraction of lowgrade, massive ore bodies with the following characteristics. Maakt het mogelijk om pdfbestanden samen te voegen met een simpele drag anddrop interface. The second section describes underground mining equipment, with particular focus on excavation machinery such as boomheaders, coal cutters, continuous miners and shearers.
The mining rate is greater than 20,000 tonnes per day tpd but is usually much greater. A prognosis methodology for underground infrastructure. In this method, the ore is excavated in open stopes, retreating from one end of the stope toward the other. The production for a mine using sublevel stoping can range from 15 40 tonsemployeeshift, while one stope can produce greater than 25000 tons per month. This method owes the first part of its name to the fact that work is carried out on many intermediate levels that is, sublevels between the main levels. Block caving is the logical stepup of sublevel caving. Sublevel caving can be used in orebodies with very different properties and is an easy method to mechanize. For sublevel stoping the ore body and walls should be strong enough to support open stoping. Upslope and specific catchment areas are deterministic quantities that we should be able to compute in a repeatable way.
Dec 01, 2016 sublevelcavingmethod newtrax technologies inc. Section 10 shrinkage methods mike turner australian mining. However, sublevel caving leads to greater dilution and is therefore used for lower ore bodies. The randomness in the method of fairfield and leymarie 1991 is not appealing.
Helpful article on how to merge pdf files in different ways with pdf24. As compared to other mining methods, sublevel caving allows for a quicker and less expensive mining process. The process of identifying and optimizing a method to mine the block 5 orebody started in 1991, and in 2006 incline caving was identified as being technically feasible. A prognosis methodology for underground infrastructure damage. Different failure models are investigated as a function of the orientation of the jointing pattern relative to the location and progressive development of the block cave. Oct 25, 2017 the loss and dilution of ore by sublevel caving mining method is influenced by gravity flow principles of caved granular materials rocks.
After the bottom of the block, or panel, is cut up into pillars by drifts and cross drifts, the pillars are robbed, and then the remaining stumps are. This method of estimating has the added advantage of being unaffected by inflation or deflation since current monetary val. By combined use of dimensional analysis and similitude studies in physical modelling coupled with numerical simulation, this paper reports results of a study of gravity flow of muck in. The simplest method is to use filenew document, and choose the option to combine files into a single pdf. Select merge mails into one pdf file under archive method. The block model is discretized to blocks of a userdefined size. Shabanie mine is a sublevel caving underground mining operation in zimbabwe. In any discussion of methods of underground mining comparison, one is repeatedly confronted with the difficulty of dealing with so many variable conditions.
The official publication of the newcastle and hunter valley speleological society. Jun 01, 2010 an underground mining method used in large, steeply dipping orebodies where the wall rock is of an incompetent nature. This method is normally used in massive, steeplydipping orebodies with considerable strike length, and usually has a high amount of dilution and low recoveries. This means that continuous excavation works can be ongoing at one sub level without interfering with another. A study of gravity flow principles of sublevel caving.
Combining pdfs with a zipper method is useful in a variety of. Safety issues in sublevel caving the brow, the edge of the intact rock and the broken rock mass, is the area where many safety hazards are present and is the area where hookup operations. During drawing the shearer is out of operation and is staying at the tail end of the longwall enabling maximum cross section of coal stream in the conveyor pans. Interaction between block caving and rock slope deformation. However the general decline in development rates ahead of mining. Sub level caving method block caving mining engineer. The selection of a suitable mining method for an ore deposit requires the consideration of a numerous criteria, such as mininggeological factors, economic factors and miningtechnical factors. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Weak rock mass and poor flow of material can cause excessive ore loss and dilution in sublevel caving.
Sublevel caving slc is a mass mining method based upon the utilisation of gravity. In order to solve the problem of low production capacity and poor safety conditions of sublevel caving mining at the yingfangzi. It allows ore economically valuable rock to collapse under its own weight in a controlled fashion. Sublevel stoping, cut and fill mining and sublevel caving have generally replaced shrinkage mining in australia, europe and canada. International journal of rock mechanics and mining sciences, vol 44, issue 6, pp. Introduction sublevel caving shields into coal mining was a great advance in. This method is usually considered as an alternate to sublevel caving when a lower dilution method is needed and where the rock is fairly competent. We use cookies to offer you a better experience, personalize content, tailor advertising, provide social media features, and better understand the use of our services. Utilization of these roof supports was advantageous. Mar 30, 2018 in sublevel caving slc, the caving of the hangingwall due to ore extraction emphasises placement of the mining infrastructure in the footwall.
Historical mine data withheld for proprietary reasons for the period 19902000 indicate that buffer mineral reserves have traditionally been maintained at about 4 years with the lor in excess of years. Use the mergepdfs method to merge the specified pdf files into a single output file. About copper mining and mining photo from copper mines in india by n g nair manager mines malanjkhand copper project. The d8 method does well on points 1, 4 and 5, but resolves flow directions too coarsely point 3 introducing grid bias point 2. A study of gravity flow principles of sublevel caving method. What is the difference between sublevel stopping and sublevel. Kvhpm department of mining and mine surveying, royal institute of technology, stockholm, sweden received 1 november 1965 atraetthe following article contains a summary of the results obtained by theoretical calculations, model experiments and largescale. Optimum sublevel height and drift spacing in sublevel cave. Caving mines by means of a large 3d physical model. Jun 25, 2010 sublevel caving technique published on jun 25, 2010 sublevel caving is usually carried out when mining of the orebody through an open pit method is no longer economically feasible. Sublevel caving shields and their utilization in mining out disturbed thick. This paper proposes a method to establish design parameters for an inclined deposit within a weak rock mass and evaluates its effectiveness through a case study.
The append method can be thought of as a merge where the insertion point is the end of the file. It is not an exact science and in the choice of a method each varying factor has a certain weight, which, in many cases, experience alone can determine. Numerical simulation of independent advance of ore. Pwc open pit mining mining methods 5 open pit mines are used to exploit low grade, shallow ore bodies. Caving underground mining methods longwall, sublevel caving. Caving models simulate cave flow for the lifeofmine of a caving operation for several outcomes such as recovery, dilution and production scheduling. Yamatomi encyclopedia of life support systems eolss 2. Parameters influencing full scale sublevel caving material. Mining method selection by integrated ahp and promethee. The second half of the name derives from the caving of the hanging wall and.
Project sublevel caving was carried out during the years 2009 and 2011, with a budget on 450 million nok. Justintime development model for a sublevel caving. Mining method selection by integrated ahp and promethee method. In the settings dialog box, choose a pdf version from the archive format selection box. In this section, the pdfmerger class method is presented. The footwall infrastructure must thus be positioned sufficiently far into the footwall to avoid. Sublevel caving and block caving underground mining methods presentation pdf available february 2014 with 6,829 reads how we measure reads. Classification of underground mining methods mineral production in which all extracting operations are conducted beneath the ground surface is termed underground mining. Mining method selection is the most important decision made in a mine project. Sublevel caving past and future australian centre for.
The ore deposit is developed by a series of sublevels spaced at vertical intervals of 18 to 25 ft or 30 ft 5. The ba5 and bb1e blocks figure 2 below the sill on elevations 630 mbs and 732 mbs respectively were changed from postundercut panel retreat caves to advance undercut block caves to reduce the tunnel deformation and failures caused by high abutment stresses on the production level infrastructure, which was developed and. Evolution of sublevel caving safety improvement through. The pebble limited partnership has proposed to mine pebble east using the underground block caving method, which is the cheapest way to mine underground figure 2. The method functions on the principle that ore is fragmented by blasting, while the overlying host rock fractures and caves under the action of mineinduced stresses and gravity 2. The loss and dilution of ore by sublevel caving mining method is influenced by gravity flow principles of caved granular materials rocks. Gravity flow of broken rock muck in dipping narrow veins is complex. Thedailyproduction fromcavemining operations throughout theworldisapproximately. This article discusses the system details and the impact this system can have on the slc method that is used in many underground mines throughout the world. Oct 22, 2014 sublevel stopingunderground mining methods 1. This report is advocated towards a layman in block caving in view of getting an impression about the block cave mining method. Parallel drives are developed in the ore on equally spaced levels. While the footwall in general is less affected by ground settlement compared to the hangingwall, the changes in stress field from mining are significant.
A 2d discontinuum modelling approach is utilised based on the distinctelement method. Sublevel caving technique by partha d sharma issuu. What is the difference between sublevel stopping and. The method is still used in a handful of nonmechanised mines in south america, africa, asia and canada. Apr 21, 20 a new mine planning tool for sub level caving mines gemcom. An underground mining method used in large, steeply dipping orebodies where the wall rock is of an incompetent nature. Thus sublevel caving is usually used to mine lowgrade, lowvalue orebodies. Glossary in british caving 2 nd edition 1962 an introduction to speleology. Methods of mining include stoping, caving, and various methods of working large deposits which, in addition to the method of actually breaking the ore, require elaborate and definite plans of, development of the orebody. In sublevel caving slc, the caving of the hangingwall due to ore extraction emphasises placement of the mining infrastructure in the footwall. Section 10 shrinkage methods mike turner australian. The current state of knowledge of subsidence permits a more detailed discussion of longwallinduced subsidence than of the other forms. The ore is then drilled and blasted using longholes between levels, often in a circular or fan pattern, on retreat. This material is intended for use in lectures, presentations and as handouts to students, and is provided in power point format so as to allow customization for the individual needs of course instructors.
Mechanized under ground mines, mechanized open pit mines. Sub level caving method allows working in parallel on different sub levels in the mine. Block caving is an extreme case of sublevel caving in which instead of a back of ore 5 to 10 ft. Cavingisthelowestcost underground mining method provided thatthe drawpoint sizeandhandling facilities are tailored tosuitthecavedmaterial andthatthe extraction horizon canbemaintained forthelife ofthedraw. Underground mining methods are usually employed when the depth of the deposit andor the waste to ore ratio stripping ratio are. Unesco eolss sample chapters civil engineering vol. The following method uses adobe acrobat pro dc, the best pdf editor you can download. Shrinkage mining was a common stoping method prior to mechanised mining and the introduction of hydraulic fill.
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